Long March 2D sends Yaogan Weixing 31 satellite aloft

Using a Long March 2D booster, China has successfully sent its newest Yaogan Weixing remote sensing satellite into orbit. The launch was conducted at 04:11 GMT on Sunday, December 3 (11:11 p.m. EST on Saturday, December 2), 2017, from the LC43 Launch Complex at the Jiuquan Satellite Launch Center (JSLC) in China’s Gansu Province.

The mission was originally scheduled for November, and the Long March 2D rocket was delivered to JSLC in mid-October. Details about the pre-launch preparations as well as the identity of the payload were shrouded in secrecy until Chinese media confirmed the success of the launch approximately half an hour after liftoff, noting that the Yaogan Weixing-31 spacecraft was the only passenger of Sunday’s mission.

Long March 2D / LKW-1 launch. Photo Credit: Zhen Zhe / Xinhua

Given that China has kept the details about the mission under tight wraps, the exact timeline of the flight is unknown. The Long March 2D rocket most likely flew for about 10 minutes, burning its first stage for some three minutes after liftoff. The rocket’s second stage controlled the mission for the remaining seven minutes, which ended with the insertion of the payload into a low-Earth orbit (LEO).

China insists that its newly launched spacecraft is a land-exploration satellite that will be mainly used for remote sensing exploration of land resources. However, Western analysts believe that the satellite will be employed for military purposes.

Yaogan Weixing-31, also known as Land Surveying Satellite-1, or LKW-1, was developed by the China Academy of Space Technology (CAST). It is probably an electro-optical observation satellite based on the military Jianbing-6 series. The spacecraft most likely utilizes uses the CAST-2000 platform, which has a dry mass of about one metric ton.

The first Yaogan satellite was launched in 2006, whereas the second generation of the series was inaugurated in 2008. The previous Yaogan spacecraft (Yaogan 30) was orbited on May 15, 2016.

The Long March 2D, used for Sunday’s mission, is a two-stage rocket developed by the Shanghai Academy of Spaceflight Technology. It is mainly used to launch a variety of satellites into LEO. The 135-foot (41.15-meter) tall booster can launch payloads of up to 3.9 tons (3.5 metric tons) to LEO and has a Sun-synchronous orbit (SSO) capability of up to 1.4 tons (1.3 metric tons).

The rocket was launched for the first time on August 9, 1992, from the Jiuquan Satellite Launch Center. It orbited the Fanhui Shei Weixing FSW-2-1 recoverable satellite.

Sunday’s flight was the 257th flight of the Long March rocket series. It was also the fifth orbital launch from the Jiuquan Satellite Launch Center and the 15th orbital mission for China in 2017.

China’s next flight is currently planned for December 11 when a Long March 3B rocket will deliver the Alcomsat-1 spacecraft into orbit for the Algerian Space Agency.

Tomasz Nowakowski is the owner of Astro Watch, one of the premier astronomy and science-related blogs on the internet. Nowakowski reached out to SpaceFlight Insider in an effort to have the two space-related websites collaborate. Nowakowski's generous offer was gratefully received with the two organizations now working to better relay important developments as they pertain to space exploration.